Lapping machine



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LAPPING MACHINE Filed July 22, 1950 6 Sheets-Sheet 3 0 HQE HERBERT 5'. INDEE my, Mm.etam. @bier/nag,

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June 2, 1953 H, s lNDGE 2,640,302

LAPPING MACHINE Filed July 22. 195o e sheets-sheet e I] I I me/rm HG. l E Vl--a'ERJEERT 5. INDQE Patented June 2, 1953 LAPPING MACHINE Herbert S. Indge, Westboro, Mass., assigner to Norton Company, Worcester, Mass., a corporation of Massachusetts Application July 22, 1950, Serial No. 175,452

7 Claims,

'lhe invention relates to lapping machines, and more particularly to a machine for automatically lapping the opposite faces of successive ilat workpieces to apredetermined size and nish.

One object of the invention is to provide a simple and thoroughly practical lapping machine automatically to lap the opposite plane faces of successive Workpieces to a predetermined size and finish. Another' object is to provide a lapping machine having two opposed rotatable lapping wheels and a work cage therebetween for conveying successive nat workpieces in a circular eccentric path between said wheels to simultaneously lap the opposed surfaces thereof to the required extent during a single pass through the machine. Another object is to provide an annular rotatable ring gear for supporting and driving the work cage about an axis eccentric to the axes of the lapping wheels. Another object is to provide a motor driven mechanism positively to rotate the ring gear and cage at a slow controlled rate to govern the duration of the lapping operation. A further object is to provide automatic loading and discharge mechanisms automatically to load and discharge successive workpieces from the continuously rotating work cage before and after lapping. Another object of the invention is to provide a plurality of anti-friction rollers to locate and support the ring gear in a predetermined plane normal to its axis of rotation and also to provide a rotary support thereier. it is a further object of the invention to provide an axial adjustment for one and/or both oi the lapping wheels to facilitate compensation for Wear and for truing of the lapping wheels. @ther objects will be in part obvious or in part pointed out hereinafter.

The invention accordingly consists in the features of construction, combinations of elements, and arrangements of parts, as will be exempliiied in the structure to be hereinafter described, and the scope of the application of which will be indicated in the following claims.

In the accompanying drawings, in which is shown one oi various possible embodiments of the mechanical features of this invention,

Fig. 1 is a fragmentary plan view of the lapping machine with the upper lapping wheel and its supporting and driving mechanism removed;

Fig. 2 is a staggered sectional View, taken approximately on the line 2-2 of Fig. l;

Fig. 3 is a vertical sectional view, through the lapping machine, with the work cage mechanism removed; y l

Fig. 4 is a fragmentary plan view, on an enlarged scale, taken approximately on the line 4-4 of Fig. 2, showing one of the three roller supports for the work cage driving gear;

Fig. 5 is a fragmentary sectional view, on an enlarged scale, taken approximately on the line 5-5 of Fig. ll, through one of the adjusting screws;

Fig. 6 is a fragmentary sectional view, on an enlarged scale, taken approximately on the line t--S of Fig. 2, through the bracket for supporting one set of the guide rollers for the cage driving gear;

Fig, 7 is a plan view of the parts shown in Fig. 5;

Fig. 8 is a fragmentary sectional View, takenr approximately on the line 8-8 of Fig. 7;

Fig. 9 is a fragmentary sectional View, on an enlarged scale, taken approximately on the line S-S of Fig. l, showing one of the driving connections between the work cage and its driving gear;

Fig. 10 is a fragmentary front elevation, taken approximately on the line IIJ-l0 of Fig. 1, of the work loading mechanism;

Fig. 1l is a cross-sectional View, on an enlarged scale, taken approximately on the line ll-ll of Fig. l0;

Fig. 12 is a vertical sectional view, taken approximately on the line |2--I2 of Fig. 2, through the adjustable support for the lower lapping wheel;

Fig. 13 is a fragmentary plan view, on an enlarged scale, showing the adjustably mounted loading and discharge platen;

Fig. 14 is a sectional View, taken approximately on the line lll- I4 of Fig. 13;

Fig. l5 is a fragmentary cross-sectional View, through one of the workpieces;

' Fig. 16 is a fragmentary front elevation, on

an enlarged scale, of a portion of the work load-I ing mechanism;

Fig. 17 is a plan View of the parts shown in Fig. 16;

Fig. 18 is an electrical diagram showing .the

electrical control mechanism for the work cage:

driving and work loading mechanisms.

Referring more particularly to the embodiment illustrated, the lapping machine may be constructed in its general aspects similar to the lapping machine illustrated in my prior U. S. Patent No. 2,103,984, dated December 28, 1937. This machine, as illustrated, may comprise a base I0 which rotatably supports a lower lapping wheel Il. The base It is provided with an upwardly extending column i2 having an outwardly extending hor'mohtal portion I3 which rotatably supports a vertical spindle Iii. The spindle I4 is provided at its lower end with a supporting plate I5 which carries a rotatable lapping wheel I6.

Power may be obtained from any suitable source, such as an overhead drive shaft or an electric motor mounted on the machine. For the sake of illustration, a belt drive has been shown comprising a driving belt which serves to rotate a pulley 2l. The inner portion of the pulley is formed as one part of a cone clutch. A slidably mounted clutch member 22 serves to cooperate to permit power to be readily connected or disconnected. The pulley 2| is rotatn ably supported on a horizontallyextending shaft 23 which is supported in bearings 24, 25, 25 and 21 in the base ie. The clutch member 22 is slidably keyed to the shaft 23. When the clutch is in full line position as indicated in Fig. 3, no power is transmitted to the shaft 23. When it is desired to rotate the shaft 23, the cone clutch member 22 is moved toward the right (Fig. 3) into engagement with the cone clutch member within the pulley 2I so as to cause a rotation of the shaft in order that the clutch may be readily operated from the front of the machine, a pivotally mounted control lever 28 is supported on' a stud 29 on the base I0. The lower end of the lever 28 is connected by a pin 30 with -a link 3| which is connected by means of a rod 32 supported in bearings 33 and 34 with a yoked inemu ber 35 and engages a groove S5 in the hub 31 of the clutch member 22. By movement of the control lever 22 in a counterclockwise direction, the clutch member 22 may be thrown into engagement with the clutch member within the pulley 2I to cause rotation of the shaft 23. A spring pressed roller 38 cooperating with an arrow point 39 on the yoked member serves to hold the clutch either in or out of engagement.

rlhe shaft 2t is provided with a worm d5 which meshes with a worin gear 46 mounted on the lower end of a vertical shaft l. The shaft d1 is connected by a. universal joint 48 with a. shaft 49. The shaft i9 is preferably a telescopic shaft and is connected by a universal joint 5B with a vertical shaft 5I supported in bearings 52 and 53 in a bracket 5d mounted on the top of the column I2. The shaft 5i pulley 55 which is connected by belts 56 with a pulley 51 which is mounted on a rotatable sleeve 58. The sleeve 58 is slidably keyed by keys 59 to an upwardly extending projection Si] of the spindle I4, so that when the clutch 252 is engaged, the vertical spindle It supporting the upper lap ping wheel I8 will be rotated.

The bracket 54 is aidjustably mounted on the upper surface of the column I2 and is provided with a screw adjustment comprising a screw 62 which is rotatably supported in a bracket 53 fixed to the column I2 and is screw threaded into the bracket 54 so that the bracket 54 may be adjusted transversely of the machine to obtain the desired drive tension on the belts 5S.

The lower lapping wheel II is mounted on a rotatable spider which is supported on the upper end lof a vertical shaft 66. The lower end of the shaft t6 is provided with a worm gear 81 which meshes with a worm B8 mounted on the shaft 23. it will be readily apparent from the foregoing disclosure that rotary motion of the shaft 23 vwill be imparted through the driving mechanisms above described to impart a rotary motion to 'trie u'ppei' lapping Wheel I6 and the is provided with a f 4 lower lapping wheel II to rotate the lapping wheels in the opposite directions.

A suitable counter-balance mechanism is provided to counter-balance the weight of the upper lapping wheel I6 and its supporting mechanism. This mechanism is not considered a part of the present invention and consequently has not been illustrated in detail, This mechanism is identical with that shown and fully described in my prior U. S. Patent No. 2,103,984, dated December 28. 1937, to which reference may be had for details of disclosure not contained herein. f

In order to limit the downward movement of the upper lapping wheel I6, a suitable stop mechanisni is provided to positively limit the downward movement of the lapping wheel so that it bears a definite and predetermined relationship with the lower lapping wheel and the work. This stop may comprise an adjustable stop l5 which is edjustably mounted in a bracket I6 which is supported in fixed relationship with the column I2. The stop i5 is provided with a screw threaded port-ion meshing with a correspondingly threaded aperture within the bracket i6. A transversely extending clamping screw 78 is mounted within the bracket it and serves to clamp the stop I5 in adjusted position. A movable stop screw 80 is supported in a bracket 8`I adjustably llxedto an axiallv movable sleeve 'I2 which supports the spindle i4. The sleeve l2 is provided with a plu= rality of spaced threaded holes 82 so that the bracket SI may be clamped in various positions on the sleeve i2 by means of screws. The stop screw B passes through a threaded aperture lu the bracket 8l and is provided at its upper end with a graduated micrometer adjusting member 86 which enables a fine adjustment of the stop screw Si) to vary the lower position of the upper lamine wheel I6 as desired. In order that the stop screw i-l may be locked in adjusted position, the bracket 8| preferably provided with 'a slot which extends from the end of the bracket to the threaded aperture. A clamping screw 88 e'xtends transversely through the bracket 8`I at a point intermediate the slotted area and serves to bind the bracket 8l when it is desired to lock the stop screw 8i) in a predetermined adjusted position. By means of a plurality of threaded holes 82 in the sleeve 12, a quick adjustment of the bracket 8i may be obtained to vadjust theA stop in setting up the machine for lapping workpieces of varying thicknesses.

A suitable adjusting mechanism is provided for adjusting the position of the lower lapping' wheel II so as to maintain its operative face in the same plane. After normal wear of the lapping wheel or after truing operations, it is desirable to raise the lower lapping wheel II so as to reposition the plane of the operative face thereof. This is preferably accomplished by mounting the lower lapping wheel II on a plate '30 which is in turn supported on a cup-shaped housing BI having an internal thread 92 which meshes with or engages an external threaded portion 93 of a cup-shaped member 94 which is xedly mounted on the spider 65. It will be readily apparent from the foregoing disclosure that by a rotary adjustment of the cup-shaped member 9i, the lower lapping wheel II may be raised or lowered'as desired. Inoider to facilitate rotary adjustment'of the cup-shaped member "9|, a. plurality of holes 95'a`r'e provided'in the member 9| which may be engaged by a special Spanner type wrench to facilitate adjustment thereof, In order to l'o'ck'the member SI iha'djus'te'd position,

a plurality of cylindrically shaped locking members 96, 96a and 96h fit Within cylindrically shaped apertures in the member 9| and are provided with inner threaded portions 98 which mesh with or engage the external threaded surface 93 of the cup-shaped member 94. A clamping screw 99 is provided for each of the clamping members 96 by means of which the members 96 may be moved longitudinally to lock the member 9| in adjusted position on the member 94.

In order to automatically lap a plurality of successive workpieces to the desired and predetermined extent, a Work cage is provided comprising a disc-shaped work cage having a plurality of work receiving apertures |0 The work cage |00 is preferably supported by an annular ring gear |02. The ring gear |02 is provided with a recess |03 to receive the work cage |00. In order to drive the work cage |00 with the gear |02, a plurality of driving pins |04, |04a and |04b are ilxedly mounted on the ring gear |02. The pins |04 are arranged to engage radial slots |05, |05@ and |05b formed in the periphery of the work cage |00.

The ring gear |02 and the work cage |00 are preferably supported to rotate about an axis eccentric relative to the axes of the upper lapping wheel |6 and the lower lapping wheel so that, as shown in Fig. l, the workpiece engages the throat between the upper lapping wheel |6 and the lower lapping wheel and travels in a circular path eccentric to the axes of the lapping wheels so that the workpieces travel from an entering point where they engage the lapping wheels at their peripheries and pass across the entire face of the lapping wheel so that at a midway point the workpieces move so that they engage the inner portions of the lapping wheels after which they again continue in a circular path to the outer peripheries thereof. Due to the opposite rotation of the lapping wheels and also due to the path of movement of the workpiece across the plane faces of the two Wheels, the workpieces are caused to rotate within the apertures |0| so as to produce the desired relative motion to lap the opposite surfaces thereof to a predetermined size and finish.

A suitable supporting and driving mechanism is provided for supporting the ring gear |02 and the cage |00 in a predetermined plane. The base |0 serves as a support for a pan ||0 (Fig. 2) which serves as a support for a pair of vertically arranged rods and ||2 (Fig. l) which serve as supports for brackets ||3 and ||4 respectively. The rods and ||2 are adjustably mounted on the pan ||0. The rods pass through a cylindrical aperture ||5 in brackets ||6 and ||1 which are adjustably fastened to the pan ||0 by means of screws H8, ||9, |20 and |2|. The brackets ||6 and ||1 are slotted and provided with clamping screws |22 to facilitate clamping the rods and ||2 in adjusted position. The bracket ||3 ls provided with a pair of rollers |25 and |26 which engage the inner peripheral surface of the ring gear |02 to form an anti-friction support therefor. The bracket ||3 is also provided with a roller |21 which engages the under-surface of the ring gear |02 to form a support therefor. lSimilarly the bracket |4 is provided with a pair of rollers |28 and |29 which are arranged to engage the inner peripheral surface of the ring gear |02. The bracket ||4 is also provided with a roller |30 which engages and supports the under-side of the ring gear |02. also provided with a bracket |35 (Fig. 2) which The pan ||0 is j is similarly provided with a pair of rollers |36 and |31 which engage the inner peripheral surface of the ring gear |02. The bracket |35 also supports a pair of rollers |38 and |39 which engage the under-side of the ring gear |02 and which cooperate with the rollers previously described to support and determine the path of rotation of the ring gear |02 which rotates about an axis eccentric to the axes of the lapping wheels I6 and The bracket |35 is adjustable in a transverse direction to facilitate adjustment of the position of the rollers in setting up the machine. The bracket |35 is provided with a pair of elongated slots |40 and |4| (Fig. 4). Clamping screws |42 and |43 pass through the elongated slots |40 and |4| respectively and are screw threaded into a bracket |44 which is adjustably mounted on the outer peripheral surn face of the pan ||0 by means of screws |45 and |46. By adjustment of the position of the brackets ||3 and ||4 and |35, the position of the guiding rollers |25, |26, |28, |29, |36 and |31 may be varied to determine the position of the path of rotary movement of the ring gear |02. By a vertical adjustment of the brackets ||3, ||4 and |35, the rollers |21, |30, |38 and |39 may be adjusted to determine the plane of rotation of the ring gear |02 and the cage |00.

Each of the adjusting screws ||8, H9, |20, |2|, |45 andV |46 are provided with a push and pull adjustment as illustrated in Fig. 5. The clamping screw |46 is screw threaded into the pan |10. The screw |46 passes through a central aperture |41 in a threaded sleeve |40. The sleeve |48 is screw threaded into the bracket |44. The righthand end of the threaded sleeve |40 bears against a plane surface on the pan ||0. The lock nut |49 is provided lfor locking the threaded sleeve |48 in adjusted position. It will be readily apparent from the foregoing disclosure that by loosening the screw |46 the threaded sleeve |48 may be adjusted in either direction lto move the bracket |44 either toward or from the outer peripheral surface of the pan ||0 after which the clamping screw |46 may be again tightened and the lock nut |49 locked.

A driving mechanism is provided for rotating the ring .gear |02 and the work cage |00 at a relatively slow speed to produce the desired lapping action. This mechanism may comprise an electric motor having an integral speed reduction unit |6| xedly attached thereto. This motor driven gear reduction unit may be any of the standard well known mechanisms such as are now available. The motor speed reduction unit is mounted on the bracket |44 which as previously explained is adjustably mounted on the pan ||0. The speed-reduction unit |6| is provided with a driven shaft |62 having a gear |63 which meshes with a gear |64 mounted on a rotatable shaft |65. The shaft |65 is provided with a gear |66 which meshes with the ring gear |02. It will .be readily apparent from the forelgoing disclosure that rotary motion of the motor |60 and the speed reduction unit 6| will 'be imparted torotate the ringlgear |02 and the cage |00 at a relatively slow speed. If different speeds are desired, the gears |63 and |64 may be changed to provide either an increased or a decreased speed of the ring gear |02.

It is desirable to provide an automatically operated work loading mechanism for automatically conveying successive workpieces to the holes or pockets |0| in thework cage I 00. The partcular workpiece illustrated in drawings has .been illustrated inFig. '15. This' .workpiece s'n the 7 form of aV washer |68 havinga central hole |69.

An upwardly extending flange |10 projects from. A recess I1 I be a hopper typeieeding mechanismsuch as for example that manufactured by the Detroit Power Screwdriver Company or Detroit, Michigan, and disclosed in U.S. Patent No. 2,350,486 to R. W. Bailey, dated. June 6, 1944I to which reference may be had for details ofy disclosure not. contained herein. This work feeding; mechanism may comprise, a rotatable hopper which is driven by an electric motor ll'tln'ough a worm and worm gear unitcontained within the casing ITI; which is in turn adjustably mounted on a vertically extending rod |19. The rod |18 is adjustably clamped in bracket Ill which. is ias tenedA to the bracket |44'. Thel bracket ML as above de eribed is adjustably mounted on the outer periphery ofthe pan I I0.

sired position. Clamping screws |83 and |84 are provided on the bracket ITB-to facilitate clamping;l the bracket |153. in the desired adiustedposition ou the-rod |19. The rotary hopper. wheel serves to pick up washers ISS to be lapped in an inverted position as illustrated in Fig. 15. and to pass the washers through a loading chute IE5 which turns the washers ISI?y into an upright positionA for loading` into apertures IU'I of the cage |00. The` loading chute |85 is provided with aT-shaped-clearanceslot lthrough which the workplaces slideonto-the upper surface oi' the work cage Iii. Ater leavingthechute |85, the workpieces pass through a box-like chute |81 havingI a plurality of adjustably mounted fiat. springs |28I Iland |96 which .serve to hold the workpieces downwardly and to reta-rd the movement of the Workpieces until they drop into the holes IUI in. the work cage |00. Thetension of the sprirrgs |88, i321. and ISS. may be adjusted by means or" set screws ISI, |92 and |93 respectively. A. guide plate 2.02 is mounted on one. side of the chute |81 to facilitate. guidingtheworkpieces ISB .into the path of. the. apertures IIlI4 in the Work cage IGH.

A. suitable safety device is provided t0. stop the rotation oi' the,r ring` gear |82 and the work cage IIlU and also. to stop the worl; loader` |15 in case the washers are not in proper `position and in case they do. not fall into theA holesv IOIfin the cage IDD. This mechanism may comprise a lever ISA which is pivotally mounted on studs |95' carried by a. bracket |96. The normalv position of the lever |94 is determined by; the setting of a stop. screw |1 which isV supported .by an arm ISE carried by thebracket I 96. If the workpieces ISB fail to. drop.4 into'the. holes` IUI inthe work cage` |90, the protruding workpieces will. engage the under-surface. of the lever |94. and rock. the lever llll` in a,- counter-clockwise direction (Fig. 16) about pivot studs |95. Theother end-'of the lever |94 is provided Witha set screw |99' which is arranged to` engagek the actuating'plunger 200 ol a normally closedlimit switch Rocking movement of the lever I94ina counter-clockwise direction will serve in case the workpieces |68 are not properly located within'v the cage apertures IDI to open the, limit switch 20| and. thereby to stop, the rotation of the; motor IBI), therebystoppingl the rotary'niotionz of the ring gear. |l'I2v and This assembly mountedzon a bracket. |13*V Clamping screws. ISI and |82 serve to clamp therod ITS in the de the work cagev Ill to prevent damageto the machine by improperly positioned workpieces.

The automatic work loader |15 is arranged to pick up workpieces and to position them in the proper position in the chute so that the flanged portion I1|l4 Will be upward when the workpiece is placed. in the apertures IUI of the work cage I 00.

Asshown in Figs. l, 13 and lll, workplaces |58 are loaded into the apertures IDI of the cage IEID at a point outside the periphery of the lapping wheels I6 and II. It is therefore desirable to provide an arcuate shaped loadiugplatform 235 adjacentto the periphery of the lower lapping wheel Il having an upper surface which lies in the same plane with the operative face ci the lapping; wheel II. The loading platform 265 is provided with a downwardly extending' integral bracket 256 which is fastened by two pairs oi" adjusting screws '231 and 263 to the pan I Ill. The adjusting screws l and 238. are identical with that shown in 'l-'tw 4 and comprise means whereby the bracket 2% maybe adjusted in a vertical plane to align the upper operative surface of the loading platform 265 in a horizontal plane.

'ln setting' up the machine, the lower 'lapping wheel I| may oe adjusted vertically so that its upper or operative surface lies. in the saine plane with the loading platform 2t5. It will be readfily apparent from the foregoing disclosure that worlipieces load nto the apertures II ol the IUD are cai -d alc-ng the operative face oi the loading platrorzn into engagement with the throat formed between the upper lapping wheel. Iii and the lower lapping wheel i. as shown Fig. i rotation o the page IlB at a slow rate of .speed causes the workpieces to travel in a circular path eccentric to the axes oi the lapping wheels IS and Il, so that the worlpieces travel from the outer peripheral surfaces of the lappingwheels l5 and II to the inner. surfaces thereof after which they again travel across the faces. of the wheels to the outer peripheries thereof. At 'this point the finished lapped wol-ll:-

.. pieces ride onto and are supported by the load ing platform '255. lli/hen the lapped workpieces successively reach an aperture ZUG formed in the loading` platform 7225, they drop through the ldl'lg platform onto an inclined surface 2 i 0 and onto an inclined chute 2| I into a container 2|2. It will be readily apparent from the foredisciosure that workpieces automatically loaded by the motor driven work loader |15 are automatically fed to the apertures Il of the rcage IIJ after which the workpieces make one circular path through the throat between the lapping wheels I5 and II during which time the upper and lower faces of the workpiece are lapped to the desired'and predetermined extent. After one complete pass between the wheels, the workpieces |68 are automatically discharged from the cage IUD and slide downwardly into a receivingcontainer 2|2 (Figs. 13 and.14).

During the passage of the workpieces between the grinding wheels, due to the oppositely rotating lapping wheels and the eccentric circular path through which the workpieces travel, a rotary motion is imparted to the workpieces relative to the lappingr wheels so that a desired and predetermined lapping operation is simultaneously performed on the opposite faces thereof. In lapping the 'type of workpiece such as shown in Fig. 15, a relatively large area. on the lower surface is lapped whereas a relatively small area on the upper. surface. is simultaneously lapped.

-9 If desired, lapping wheels of varying grit size or grade may be utilized to oiTset the. differences in areas to be lapped so that a desired and uni form lapping operation is obtained on both surfaces.

Referring now to Fig. 18, an electrical diagram has been illustrated to show the operation of the safety device in connection with the work loader. Electric power is supplied through the power lines Li, L2 and L3. A main switch 2|5 is provided for connecting power with a magnetic switch 2|6 for controlling the work cage driving motor |60 and the work loader driving motor |16. A low voltage current is provided for the control circuit. A transformer 2V! has its primary circuit connected with the power lines Ll and L3. The secondary circuit thereof is connected through a starter switch 2 8 to close a circuit so as to energize the magnetic starter switch 2 I B so as to start the motors |50 and ll. A. holding circuit serves to maintain themagnetic starter switch 2|6 closed. A stop switch 2|9 is provided whereby the circuit may be broken to deenergize the magnetic starter switch 2 l0 when desired to stop the cage driving motor |60 and the work loader driving motor |15. The normally closed limit switch 20| is connected in the control circuit so that if and when the limit switch 20| is opened in case workpieces do not properly locate in the work cage, the opening of the. limit switch 20| will serve to deenergize the magnetic starter switch 2|6 thereby stopping the cage driving motor |60 and the work loader driving Amotor |16.

The operation of this improved lapping machine will be readily apparent from the foregoing disclosure. Assuming all of the adjustments to have been previously made and the operative faces of the lapping wheels trued to parallel plane surfaces, a plurality of workpieces are placed within the automatic motor driven work loader |15.v The workpieces are automatically fed by the loader |15 into the chute |85 into engagement with the apertures |0| of the work cage |00. Due to the relatively slow rotary motion of the cage and its driving gear |32, the workpieces are successively carried in a single circular eccentric path through a lapping throat formed between the lapping wheels le and to lap the opposed surfaces thereof to a predetermined size and finish. After one complete pass between the wheels the workpieces are then automatically discharged into the receiving container 2 |2.

If either of the lapping wheels become worn away or require truing, a truing operation is performed in the conventional manner by means of a truing mechanism such as that shown in my prior U. S. Patent No. 2,082,736, dated June 1, 1937 to which reference may be had for details of disclosure not contained herein. After truing of either or both of the wheels, it is then necessary to readjust the stop 80 for the upper lapping wheel I6 to allow the lapping wheel to resume a normal operating position relative to the work cage |00. It is also necessary to vertically adjust the lower lapping wheel in a ymanner above described to reposition the operative face thereof in a plane coinciding with the plane of the loading platform 205. It will be readily appreciated from the foregoing disclosure that the cage |00 and its supporting gear |02 is never changed or adjusted after` the initial setup but the lapping Wheels are adjusted to compensate for `wear or truing.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a lapping machine having a base, a pair of vertical axially aligned rotatable spindles on said base, a pair of rotatable lapping annuli each having a plane operative face mounted on the adjacent ends of said spindles, means including a slidably mounted sleeve on said base rotatably to support one ofsaid spindles, means including an adjustable stop on said sleeve to facilitate maintaining said lapping faces a predetermined distance from each other during the entire lapping operation, a work support including an annular gear surrounding the lower lapping annulus, a work cage having a plurality of work receiving apertures supported by said annular gear and positioned between. the opposite faces of said annuli, means including a plurality of symmetrically arranged rollers on said base rotatably to support said annular gear, said rollers being arranged so that the gear and cage rotate about an axis off-set relative to the axes 0f said annuli, and means including a motor driven gear reduction driving mechanism on said base having a driven gear meshing with said annular gear so as to rotate the cage at a slow speed to carry work pieces between the lapping annuli in a circular` path eccentric to the lapping annuli.

2. In a lapping machine as claimed in claim 1, in combination with the Darts and features therein specified of an automatically operated work loading apparatus supported on said base, a chute connected with said loading apparatus to convey workpieces from said apparatus to apertures in the work cage, a motor on said base to drive said loading apparatus, guiding means supported by the vbase to guide workpieces from said chute into alignment with the apertures in said cage, a limit switch supported in fixed relation with said chute which is operatively connected to stop both the cage driving and the loading apparatus motors when closed, and a trip finger pivotallysupported on said chute in a position to be actuated by workpieces failing to drop into the cage apertures to actuate said switch so as to stop both the work loader motor and the cage driving motor.

3. In a lapping machine as claimed in claim 1, in combination with the parts and features therein specified of an automatically operated motor driven work loading apparatus, a work chute between the loading apparatus and cage to convey workpieces from said apparatus to aperturesl in the work. cage, guiding means on said base to guide workpieces from said chute into alignment with the cage apertures, a plurality of spring lingers supported by said guiding means with, said guiding means to facilitate locating successive workpieces in cage apertures, a limit switch on said chute which is operatively connected to stop both the cage driving and the loading motors when closed, and a trip finger pivotally mounted adjacent to the discharge end of said chute in a position to be actuated by workpieces failing to drop into the cage apertures to 1'1 stop both the work loader .motor and the cage driving motor.

4. .In a lapping machine having a base, a pair of vertical axially aligned `spindles on said ibase, a pair of rotatable lapping annuli each having Aplane operative faces mounted on the adjacent ends of said spindles, means onsaid base to rotate said spindles in opposite directions, a work sup* port comprising a relatively large ring gear rotatably supported relative to thebase, a cage receiving aperture on said ring gear, a work cage supported in said aperture having ra plurality of .spaced work receiving apertures, means including driving lugs on said gear to rotate .said cage, said cage and ring gear being arranged to rotate about an axis off-,set Vrelative to the axes of the lapping annuli, means including a motor driven mech.u

anism to rotate said ring geai` at a slow speed,

thework apertures being Varranged to pass-successive workpieces in an arcuate path between the operative faces of saidannuli so that the work- `pieces travel from .the outer periphery `to the .inner peripheres of saidannuli and then travelv `to the outer peripheries thereof, an. automatically actuated motor driven work loading mechanism includinga chute on said base to convey. successive workpieces to said cage apertures, and means including a. discharge chute on said base to discharge lapped workpieces from said cage after ,one pass through the machine.

5. In ya lapping machine having a base, a pair of oppositely rotating lapping annuli each .having vplane operative faces, a lpair of vertical axially aligned spindles on said base to support said annuli, means including e, slidably mounted sleeve on said base rotatably :to support one of said spindles, means including an adjustable stop on said sleeve toirnaintain said faces a predetermined distance from each other, a work support 'including a rotatable annular ring gear, a cage receivving recess therein, a rotatablecage in said recess having a plurality of Work receiving vapertures which is supported and driven by Vsaid ring gear, an anti-friction support including a plurality of symmetrically arranged krollers for said ring gear to support the cage to rotate in 'a horizontal fixed 4plane about an axis off-set relative to said spindles, means Aincluding a motor driven driving mechanism on said base `torotate said ring gear and cage at a slow speed vto carry successive workn pieces to be lapped in a `circular path between said annuli eccentric to the lapping annuli, and means independently to adjust both of said lapping annuli axially to maintain their operative .faces in predetermined planes relative to said cage vduring a lapping operation.

6. In a lapping machine, as claimed in claim 5,

in combination with the parts and features therein specifiedin which the anti-friction support vfor the work cage comprises aplurality of symmetrically arranged rollers in engagement with a plane face on the ring gear to support the cage and to determine its plane of rotation, and a plurality of symmetrically arranged rollers in engagement with a cylindrical face on said ring gear to determine the axis of rotation of the work cage.

7. In a lapping machine having a base, apair of vertical axially aligned spindles on said base, a pair of opposed rotatable lapping annuli each having a plane operative face mounted on adjacent ends of said spindles, means including a slidably mounted sleeve on said base rotatably to support one of said spindles, means including an adjustable stop on said sleeve to facilitate maintaining said lapping faces a predetermined distance from each other during a lapping operation, a work support including a rotatable cage between the operative faces of said lapping annuli having a plurality of worlt receiving apertures, means including an annular gear rotatably supported on said base, a cage .receiving recess on said. annular gear to `support said cage for rotation in a fixed plane about an axis oi-set relative to the axes of said spindles, means including 'a motor driven gear reduction unit on said base operatively connected to rotate said cage at a, slow speed to carry successive vwork pieces to be lapped in a lcircular path between said annuli so that the work pieces pass from the outer peripheries to the inner peripheries and to the outer peripheries thereof during a single pass therethrough, and means including a nut and screw adjusting mechanism interposed between the other spindle and lapping annulus to adjust the latter annulus relative to the base to compensate forwear so as to maintain the lapping face in a predetermined plane relative to the case.

' VHERBERT S. INDGE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 598,536 Rodd Feb, 8, 1898 703,065 Hoffmann June 24, 1902 1,551,155 Johnson Aug. 25, 1925 1,870,328 `Indge Aug. 9, 1932 1,905,651 Raule Apr, 25, 1933 1,987,674 Johnson Oct. 30, 1934 2,238,859 Indge Apr. 15, 1941 FOREIGN PATENTS Number Country Date 615,492 'Great Britain VJ an. 6, 1949 

